US Patent 8740586 Heat exchanger for ESP motor

A heat exchanger to serve ESP equipment installed on the seabed located in either a caisson or skid. A hot oil line connects the base of the ESP motor with the externally located heat exchanger, allowing hot motor oil to be circulated through coils externally exposed to seawater. The heat from the oil is rejected to the seawater and the cooled oil is reintroduced to the motor via a cold oil line that communicates with the seal section. The heat exchanger arrangement reduces the temperature of an ESP motor, thus allowing the motor to operate longer and more reliably.